Plans
to build the first database of genetic and medical information on people
of African descent were announced this week. Howard University College
of Medicine in Washington, D.C., aims to recruit 25,000 African-Americans
for the “biobank”—a resource that could be used to investigate
diseases that predominantly affect this population.

Many of the participants will initially come from the university hospital
and its affiliated clinics and physicians.

"Our patient population is predominantly African-American,"
says Georgia M. Dunston, director of the National Human Genome Center
at Howard. “We plan to investigate diseases that are common in the
African-American population such as asthma, diabetes, obesity, and hypertension.”

Scientists may stand a better chance of identifying disease genes by
studying large families and ethnic groups affected by certain diseases.
Genes discovered this way could lead to a greater understanding of disease,
or to susceptibility genes for the general population.

“We don’t expect to find a gene for asthma in African-Americans,”
says Dunston. Rather, they expect to use the biobank, which may have a
disproportionately large number of asthma suffers, to find genetic markers
associated with asthma that would apply to all people.

African-Americans, like all Americans, are a genetically diverse group,
with mixed ancestry.

The general rule of thumb in research studies is to have participants
identify their own race or ethnic background. “If someone says he
or she is African-American, then that is accepted as their ethnicity in
terms of a study,” says Robert Murray, a professor at the Howard
College of Medicine who is not involved in the biobank.

“There are no genetic markers that say a person is African or not,”
Murray adds. “Therefore the degree of precision in ethnic identity
is always going to be approximate.”

Self-identification has long been used to classify racial or religious
groups for genetic studies. This month, the North Shore Long Island Jewish
Research Institute in New York, announced plans to collect tissue samples
for studying hereditary and environmental factors involved in disease.

Decode Genetics of Iceland is collecting genealogies and DNA of Icelanders
to identify genes involved in complex diseases. Similar projects are underway
in the United Kingdom, Estonia, and other countries.

The biobank, which has not yet been funded, will be called the Genomic
Research in African Diaspora (GRAD). A private company, First Genetic
Trust in Chicago, will manage the information.